Sex-specific Impact of Computed Tomography-defined Sarcopenia on Postoperative Complications Following Elective Cardiac Surgery in Older Patients

Objectives Sex-specific differences in sarcopenia-related prognosis following cardiac surgery are unclear. We aimed to investigate the association between preoperative computed tomography (CT)-defined sarcopenia and postoperative complications in older patients undergoing elective cardiac surgeries, focusing on sex-specific differences. Methods This retrospective observational study included 133 patients aged ≥65 years who underwent elective open-heart surgeries. Sarcopenia was assessed using the psoas muscle area index derived from preoperative CT scans and defined using sex-specific cut-off values. The primary outcome was postoperative complication. Results Forty-nine (36.8%) patients had sarcopenia. Although the incidence of complications was higher in this group, the difference was not statistically significant between the groups. Multivariate logistic regression analysis excluding patients with pre-existing atrial fibrillation revealed that sarcopenia was independently associated with a higher risk of postoperative complications (odds ratio 3.73, 95% confidence interval 1.49–9.84, P=0.006). The male patients with sarcopenia showed a higher incidence of complications versus those without (56.8% vs. 33.9%, P=0.046), whereas no association was observed in the female patients. Sex-stratified analyses confirmed the independent prognostic value of sarcopenia in male patients only (odds ratio 2.52, 95% confidence interval 1.08–6.01, P=0.033). Conclusion Preoperative CT-defined sarcopenia was independently associated with postoperative complications in older male patients undergoing elective cardiac surgeries, but not in female patients. These findings suggest that the prognostic significance of sarcopenia is sex-specific, and highlight the importance of sex-specific risk stratification strategies in older patient populations undergoing cardiac surgeries.